Method of forming an article of sheet metal



W, H.. NEEDHAM. METHOD OF FORMING AN ARTICLE OF SHEET METAL.

APPLICATION FILED SEPT. 10, I919.

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sra'rns WILLIAM H. NEEDHAIVI, OF WORCESTER,

MASSACE'USETTS, ASSIGNOE TO BOSTON PRESSED METAL COMPANY, OF WORCESTER, MASSACHUSETTS, A CORPORATION OF MAINE.

Application filed. September 10, 1919. Serial No. 322,807.

T 0 all whom it may concern Be it known that 1 WILLIAM 1I.NEEDHAM, a citizen of the United States, residing at lVorcester, in the county of lVorcester and State of Massachusetts, have invented a new and useful Method of Forming an Article of Sheet Metal, of which the followingis a specification.

This invention relates to the art of sheet metal working, and particularly to a method of forming articles of a certain type from sheet metal blanks. The articles are of unusual and diflicult shape for sheet metal production and a series of unusual and novel operations are involved in the production thereof.

My invention consists in the method of producing sheet metal articles of this general type by the series of operations hereinafter described and more particularly pointed out in the appended claims.

The several steps in the production of the finished article are shown in the drawings, together with certain of the tools employed in carrying out the improved method of manufacture.

Figs. 1 to 8 inclusive are side elevations, partly in section, of the article at dilierent stages of its production;

Fig. 9 is a side elevation of the finished article, and

Figs. 10, 11 and 12 are sectional views illustrating the tools used in certain steps of. the manufacture.

The particular article taken for illustration is a ball seat, commonly used in the steering connection of an automobile, the cross section and final appearance of the article being shown in Figs. 8 and 9.

In producing this article, I take a round blank of sheet metal and by usual drawing operations transform the blank successively to the cup-like shapes shown in Figs. 1 and 2. Fig. 10 illustrates a pair of drawing dies suitable for these first operations.

The blank shown in Fig. 2 is then preterably squared off at its open end, as indicated in Fig. 3, after which it is subjected to a series of pressing operations by which the cylindrical wall of the open end of the cup is successively reduced in diameter, as shown in Figs. 4, 5, 6 and 7, while at the same time the diameter of the intermediate portion of the cup is maintained substantially constant.

The operations illustrated in Figs. 4.- to 7 inclusive, are preferably performed with Specification of Letters Patent. Patented Aug. 29, 1922.

the article inverted. Fig. 11 shows the cup I of Fig. 3 inverted, and placed in the enlarged upper portion 20 of the die 21. The I i plunger 22 then descends, forcing the blank into the narrow or contracted lowerportion to produce the successive reductions indicated in Figs. 4 to 7 inclusive.

The blank is then placed in a die of the general shape indicated at 24 inFig. 12 and a plunger 25 forces the reduced upper end of the blank against the bottom of the cup, while at the same time, the bottom is forced against the convex surface 26 in the die 24-. This operation forces the metal to the position indicated in sectional view in Fig. 8, the finished article having the general outline of Fig. 9.

I thus form from a fiat sheet metal blank an article having a strongly reinforced ball seat 80 and a much-reduced cylindrical neck 31, togetherwith a flat shoulder 82 against which the article may be firmly seated.

While I have indicated and describedmy improved method in connection with a sin gle article it will be obvious that other articles oi similar outline may be produced by this same method, and accordingly I do not wish to be limited to the details herein dis closed otherwise than as set forth. in the claims, but what I claim is 1. The method of forming an article from sheet metal, which consists in taking a sheet metal blank, drawing the same to the form of an open cup, successively reducing the cylindrical diameter of the cup, adjacent the open end only, and finally forcing the reduced portion axially against the bottom of the cup and simultaneously shaping the latter to form a ball-seat. I

2. The method of forming an article from sheet metal,-which consists in taking a sheet metal blank, drawing the same'to the form of an open cup, successively reducing the cylindrical diameter of the cup, adjacent the open end only, and finally forcing the reduced portion axially against the bottom of the cup and shaping the latterto form a ball-seat. H

In testimony whereof I have hereunto aiiixed my signature. 

